1. Field of the Invention
The present invention relates to a video recording and playing apparatus having a time shift function.
2. Background Information
As with a hard disk recorder, a time shift function is provided in some video recording and playing apparatuses that record and play broadcast data including video images such as a television program. The time shift function is a function by which broadcast data that is inputted from an external source is temporarily recorded in a specific recording region of a hard disk up to a predetermined period of time, while allowing certain processes to be performed on the recorded data. For instance, this time shift function allows the data that has been temporarily recorded in the predetermined region of the hard disk to be read and played for up to the above-mentioned predetermined time, and also allows the data being played to be fast-forwarded, rewound, paused, and so forth. The predetermined region of the hard disk where data is recorded by the time shift function (hereinafter referred to as the time shift recording region) is used as a ring buffer. Accordingly, when data corresponding to the predetermined amount of time has been recorded, any subsequent data is recorded over the oldest recorded data in the ring buffer. The purpose of allowing data to be temporarily recorded in the time shift recording region in this manner is to utilize the recording region of the hard disk more effectively.
With an apparatus having the time shift function as described above, when the record button is pressed or when the recording start time of a timer recording function comes, broadcast data is usually permanently recorded in a region (hereinafter referred to as the permanent recording region) separate from the above-mentioned time shift recording region. The reason why the data recording region for permanent recording and the data recording region of time shift recording are separately provided is because the time shift recording region is used as a ring buffer. Therefore, if the data is recorded in this time shift recording region for the purpose of permanent recording, the data will be written over after a while and cannot be stored permanently.
It has been known to permanently record data that has been temporarily recorded during the time shift operation. Such technology by which data is permanently recorded after the data has been temporarily recorded during the time shift operation is disclosed in Japanese Laid-Open Patent Application 2003-134464 and Japanese Laid-Open Patent Application 2002-354423. In Japanese Laid-Open Patent Application 2003-134464, when the record button is pressed during the time shift operation, the recording of data in the time shift recording region is stopped, and the recording of data in the permanent recording region is started. After the recording of data in the permanent recording region ends, the data that was recorded in the time shift recording region between the time at which a time shift function such as playing the data recorded in the time shift region was started and the time when the recording of data in the permanent recording region started is transferred to the permanent recording region. As a result, the data corresponding to this time period is permanently recorded without any omission. Japanese Laid-Open Patent Application 2002-354423 discloses a personal computer hard disk in which the data recording region does not have separate regions for the permanent recording and the time shift recording, and instead the recordings is performed continuously in one region, and when a request for the permanent recording of data is received during a time shift operation, the time shift data that has already been recorded is converted into data for permanent recording, such that the data is permanently recorded.
With a conventional apparatus having a time shift function, when there is a command from the record button or a timer recording function to permanently record data during the playing of the time shift operation, the recording of data in the time shift recording region is stopped and the permanent recording of data in the permanent recording region is started, as in the above-mentioned Japanese Laid-Open Patent Application 2003-134464. The problem, however, is that when the data recording position suddenly jumps from the time shift recording region to the permanent recording region in this way, the data that was recorded in the time shift recording region is cut off at the point where the data recording in the permanent recording region started, and the playing of the data recorded in the time shift recording region is forcibly stopped at this point while playing data in the time shift recording region. Another problem is that, if the data corresponding to the time between the start of the time shift operation and the time when the permanent recording starts is transferred to the permanent recording region, the transferred data can be subsequently played, but it is impossible to access the data recorded prior to the recording of the transferred data. It is also not possible to play data with the time shift operation during the permanent recording. Also, if, as in the computer hard disk of Japanese Laid-Open Patent Application 2002-354423, data is recorded continuously in the same region both during the time shift recording and the permanent recording, the data can be played with the time shift operation even after the permanent recording is started. In a conventional video recording and playing apparatus, however, since data is pre-configured to be recorded in separate regions during time shift recording and during permanent recording, these two types of data cannot be recorded continuously.
In view of the above, it will be apparent to those skilled in the art from this disclosure that there exists a need for an improved a video recording and playback apparatus that overcomes the problems of the conventional art. This invention addresses this need in the art as well as other needs, which will become apparent to those skilled in the art from this disclosure.